misfiring
 

Hi I have just acquired a rover 75 CONNOISSEUR AUTOv6 2.5 it hasnt had much care I started by taking out the front spark plugs but the leads were difficult to move with the plastic tops breaking away, also checking the drain holes by the pollen filter and ecu which i discounnected, the trouble is now the engine is misfiring could this be due to the plug leads or disturbing the ecu.any help please roger